Anesthesia systems are used, in general, to provide and dispense inhalation anesthetics for the purpose of anesthetizing patients, on which surgical procedures will be performed, in order to thus eliminate or reduce pain sensation. Mainly anesthetics in the vapor form are used in medical technology for anesthetizing patients during a surgical procedure. The prior-art anesthetic dispensing devices necessary for this and the anesthetic evaporators contained therein usually operate purely passively (with the exception of dispensing devices for desflurane), have no electronic interfaces and can be detachably or replaceably coupled with a corresponding anesthesia apparatus by means of standardized coupling devices.
In addition, electronic anesthesia systems are known, in which the anesthetic dispensing device is integrated in the anesthesia apparatus. The anesthetic dispensing device is monitored and controlled in these systems by the anesthesia apparatus itself, which has active, electronically controlled actuators as well as display means for the operating states. However, these systems have the drawback that the anesthetic dispensing device cannot be replaced in a simple manner when the anesthetic reserve has been used up. It is sometimes necessary in the course of anesthesia to replace the anesthetic. However, the dispensing device must be replaced with another dispensing device for this purpose. If a plurality of dispensing devices can be connected to the anesthesia apparatus, it is alternatively possible to change over from one dispensing device to the other. This can be achieved with the integrated systems at a great technical effort only at best.
While the patient data and relevant set parameters are displayed in the medical devices commonly used in the field of surgery usually either on luminescent displays or by means of optically active components (e.g., LEDs, seven-segment displays, etc.), such display means have not been known so far in connection with anesthetic dispensing devices. The parameters important for the monitoring and control of anesthesia, for example, anesthetic filling level and anesthetic concentration, can therefore be read only uncomfortably at best in the operating room or in a darkened environment in case of prior-art dispensing devices. Moreover, states of alarm are usually displayed on a central screen only. Direct assignment of the alarm to the component that causes the disturbance is not given or is insufficient.
In addition, other, essentially passively operating devices or device parts are in use, which lack a suitable electronic connection to a controlling device in order to make it possible, for example, to display alarm situations on site. This applies, for example, to pulmotors, flexible tube connections, syringe actuators, means for drop infusion, etc. In case of error, it would be helpful for the hospital staff to have the cause of error visualized directly at the site of the error in this case as well.
DE 38 13 520 A1 pertains generally to coding methods and coding devices for an anesthesia means as well as to the automatic recognition of an anesthetic evaporator and of the anesthetic being used. The anesthesia means contains the anesthesia apparatus proper and an anesthetic evaporator with a corresponding setting device. The anesthesia apparatus is provided with three reflective photoelectric cells, which are designed to send light signals, which are reflected by corresponding reflective marks (depending on the color thereof), which are arranged at an anesthetic evaporator coupled with the anesthesia apparatus. The light signals reflected by the reflective marks are detected by the reflective photoelectric cells, and the corresponding electric signals are sent to a measuring and monitoring unit for analysis. The type of anesthetic evaporator can be detected in this manner. Another recorder in the form of three strips arranged one above the other, on which a coding each, marked by white and black fields, is applied, is provided on the setting device designed as a handwheel for recognizing the anesthetic concentration set. The coding of the strips is entered by a scanning device by irradiating the strips with light beams through photoelectric cells in the anesthesia apparatus. The light beams are reflected when falling on a white surface and absorbed when falling on a black surface. The resulting electric signals are sent via a signal line to the same measuring and monitoring unit.
DE 10 2007 014 838 B3 describes an anesthesia system, which has an anesthesia apparatus, an anesthetic dispenser with an anesthetic reservoir, a dispensing parameter detection means and a contactless interface between the anesthesia apparatus and the anesthetic dispenser. The transmission of data (for example, anesthetic filling level) from the anesthetic dispenser to the anesthesia apparatus as well as the transmission of energy from the anesthesia apparatus to the anesthetic dispenser take place by means of electromagnetic fields. The measurement of the anesthetic filling level is performed by means of a glass tube, which is coupled with the anesthetic reservoir and is provided with capacitor surfaces, the anesthetic acting as a dielectric and a change in the anesthetic filling level in the glass tube leading to a corresponding change in capacity. The anesthetic concentration is set by means of a setting wheel on the anesthetic dispenser. The setting angle of the setting wheel is detected by means of an angle detection means, which is designed as an optical encoder.
Measures or means for visually displaying, for example, the position of the setting wheel for setting the concentration or the anesthetic filling level directly at the anesthetic dispensing device for being recognized by human operators (for example, the anesthesiologist) quickly and reliably even under poor lighting conditions, are not disclosed either in DE 38 13 520 A1 or DE 10 2007 014 838 B3.
The embodiments proposed in the state of the art make possible only an optoelectronic detection of various parameters, such as the filling level and anesthetic concentration, an anesthetic dispensing device and a corresponding anesthetic evaporator. Visual detection of these parameters directly at the dispensing device by human operators is hardly possible or requires increased attention, which is not always given uniformly due to stress during, for example, a longer-lasting anesthesia.